Jazakallah for your great effort.
The Prophet (sallallahu alaihi wa sallam) offered the salatul janaza of An-Najashi (the king of Abyssinia) – although it apparently seemed that his corpse was not present – because his corpse was brought infront of the Prophet (sallallahu wa alaihi wa sallam) as a way of miracle when he led the salatul janaza. Many sahabah witnessed this miraculous event. A similar miraculous event occurred when the Prophet (sallallahu alaihi wa sallam) offered the salatul janaza of Mu’awiyah ibn Mu’awiyah al-Muzani (Radiyallahu Anhu). Hence, it is not correct to use these two incidents to justify offering the salatul janaza of a deceased person when his corpse is not present infront of the imam.
(I’laa’ as-Sunan: 8/283; Imdaad al-Fattaah: 581; Badaa’i’ as-Sanaa’i’: 1/462)
Mufti Faizal Riza